Implement timer

[zkayser]

This may end up being larger than just a single card, but the timer should work like this:

1. The server has a timer that is constantly running.
2. Games will run for 5 minutes (may change this later) for one round
3. There will be a 30 second break period between rounds
4. The timer should be synced between client and server, with the client starting its own timer on round start and break start, synchronizing with the server every 30 seconds by pulling the current time from the server via channels.